Saturday: Hili dialogue

May 28, 2016 • 7:00 am

I am comfortably ensconced in the Hyatt McCormick Place in Chicago: the first time in my life I’ve ever stayed in a hotel where I live. But it’s convenient to the American Humanist Association annual meeting, and they’re putting me up for two nights. It’s Caturday, May 28, 2016, and, on this day in 1892, the intrepid John Muir organized the Sierra Club in San Francisco. On this day in 1934, the Dionne Quintuplets were born in Ontario: the first quintuplets in history which were known to have all survived. (They were all female, and genetically identical.) Now that multiple births are common (weren’t seven or eight just produced in one litter, though non-identical?), it’s hard to realize what a big deal this was then. Here they are. Note that they don’t look exactly the same: surely the result of epigenetics (ONLY KIDDING!):

Dionnequints2

On this day in 1937, the Volkswagen company was founded, and, in 1952, Greek women finally got the right to vote.

Notables born on this day include Louis Agassiz (1807) who founded the Museum of Comparative Zoology at Harvard, where I got my Ph.D. Sadly, he was a lifelong opponent of Darwin’s theory of evolution. Biologist Barry Commoner was born on this day in 1917, and bassist Leland Sklar in 1947—one of the great studio musicians of rock. Those who died on this day include Anne Brontë, who died in 1849 at only 29—probably of tuberculosis. Meanwhile in Dobrzyn, Hili is wondering if cats throughout the world share the morphology of their staff:

Hili: Do Chinese cats also have narrow eyes?
A: No, why do you ask?
Hili: They could’ve had similar evolutionary pressures.

P1040301

In Polish:
Hili: Czy chińskie koty też mają skośne oczy?
Ja: Nie, dlaczego pytasz?
Hili: Mogły mieć podobne naciski ewolucyjne.
It is in fact a big mystery why morphological features of human “races” differ. Epicanthic eye folds of east Asians, which give them the appearance of narrower eyes, have been hypothesized to help keep snow and wind out of the eyes, but of course they’re found in groups, like Southeast Asians, which don’t encounter those conditions. Traits like eye shape evolved when populations were isolated geographically (within the last 60,000 years, when H. sapiens spread throughout the globe), so it may have been an adaptation that simply spread out of its snow-ridden evolutionary home and has been present ever since.  I don’t buy that, and in fact consider it, and many other traits differing among human populations, as a mystery. One idea I broach in WEIT is sexual selection: different populations simply developed different criteria of beauty as an accident, and the favored traits spread quickly through populations. But that would suggest that males and not females should differ among populations, which isn’t the case for features like hair color or eye shape. (Sexually selected traits, like the color of birds, usually differ among males but not females of related species or populations; yet human morphological traits differ for both males and females.) Perhaps it’s mutual sexual selection, then, but I digress.

And Gus got a special treat yesterday: catnip. He’s a real stoner, which you can see clearly.  As his staff notes:

The first ‘nip of the year! Gus is momentarily distracted by a bird but he loves catnip. That was only half a leaf, I have to keep the plant out of reach or there’d be nothing left.

12 thoughts on “Saturday: Hili dialogue”

  1. Yes, the McCaughey septuplets of Iowa just graduated from high school last week. Four boys and three girls.

  2. :)) Big eyes and pale skin are considered as beauty by Chinese. I was kind surprised to hear a female teacher repeatedly saying how beautiful a Chinese classmate was while I was at graduate school. The Chinese girl is considered as average look among most of the Chinese. She has narrow eyes. The narrow eyes block her to be called beauty most of the time. :)) Perhaps in the western world, almost every one has big or super big eyes, the narrow eyes are kind of special. But in China, the situation is opposite.

    Once there was a female model who became famous outside of China, say, internationally. The news came back to her homeland, Chinese newspapers flushed with news — this “so ugly”,”ugly to death”, “apologize for my appearance ” became a worldwide supermodel, can you believe it? Of cause, the supermodel has narrow eyes. 🙂

    1. But that beauty ideal is the fault of colonization by white, old males.

      I think Moran would declare “mystery traits” neutral by default. Perhaps some are? Is there a good estimate of drift vs selection outcomes in bottle necked populations?

      If Asian anatomically modern humans never bottle necked, maybe the other human populations in the mix did. Denisovans bottle necked. Not as strongly as Neanderthals for the populations that left genetic fossils in the Denisova cave, but that doesn’t mean the one that mixed into the Asian population didn’t. Et cetera for all the 3-4 populations that made up modern (South) East Asians.

      1. I should add on my 3d paragraph that it was a general observation. We know from sequencing that at least Denisovans left selected traits (height adaptation).

      3. There was something that came out a couple of moths ago, IIRC, showing that the predecessors of the population who invaded the Americas before 14 kyr ago were genetically isolated in far NE Siberia from the rest of the population for 20 or 30 kyr before the American invasion. Which is peculiar, because their closest neighbours for most of that time were the “Chinese” (or “Mongoloid” in the racial classifications of the Victorian era), but they’ve not really acquired the epicanthic fold, though they do have the high cheek bones to some degree (an adaptation to extreme cold?).
        More confusingly, the Denisovans either veered across this area from the Altai to Taiwan/ IndoChina without leaving an imprint, or were the original inhabitants and were replaced leaving only a couple of fossils at one end of their range, and genetic fossils at the other end of their range.
        I believe the genetic-approved term is “a mess”.

        1. arrgh!. Need moth-balls for my calendar, and have needed them for months.

  3. I think part of the rise in large multiple births is due to assisted reproductive technology like IVF, where implantation of more than one fertilized egg used to be common (though I think it is now much less so). There’s the (in)famous “Octo-mom” who, if I recall correctly, had sextuplets and then octuplets, both from IVF. The Dionnes were just due to splitting of one fertilized egg during development: the classic reason for identical twins.

    1. Development is a crap shot:

      “The investigators developed a technique, called haplarithmisis, which teams detection of copy number variants (numbers of copies of each chromosome or of specific DNA sequences) with SNP analysis.”

      “In the past, chimeric embryos were thought to arise only from those fertilization glitches: two sperm barrel into an egg; two very early embryos glom together; an errant polar body left after meiosis pierces a fertilized egg. But the new work reveals that weird fertilization isn’t necessary to generate the different-parented embryos – it can just happen following a normal egg-meets-sperm event. The male genome doubles in some cells, the female in others, and perhaps some cells remain normal diploid from two parents.

      “This is a novel fundamental insight into the origin of chimerism, a very rare condition in humans which can lead to birth defects,” Dr. Vermeesh said.”

      “Only 6 of the 23 embryos had all normal cells. “A staggering 39% of embryos (9/23) contain blastomeres with full genome anomalies”—extra or missing chromosome sets. Two-thirds of these had extra chromosome sets, 30 percent had losses, and 3% had all DNA from one parent.

      The SNP patterns indicated which parents had contributed which genomes to the embryos. All sorts of anomalies turned up. One 8-celled embryo had two cells that had “scattered fragments of the paternal genome and no maternal inherited DNA.” Apparently DNA from the sperm had gone on replicating even though the egg’s genome had left town. Another normally-fertilized egg had fractured into three cell lines: one chromosomally normal, one with a double dose of the maternal genome, and the other with a double dose of the paternal genome. Dividing by three had been known only in cancer cells and in cells of certain insects and crustaceans. But apparently it can happen after a normal fertilization too.

      “Miracle” isn’t in the scientific lexicon. But with everything that has to go right, chromosomally speaking, to launch an embryo on the journey of prenatal development, I find it amazing that as many as 31 healthy babies are born for every 100 fertilized eggs.

      [ http://phys.org/news/2016-05-cow-embryos-reveal-chromosome-chimera.html ]

      By the way, what does extreme abortion opponents (‘life begins at conception’) say on the actual biology?

      1. By the way, what does extreme abortion opponents (‘life begins at conception’) say on the actual biology?

        Embarrassed silence?

    2. I am breaking the rules by hogging this thread, so I’ll just point out another development gaming option (that I also didn’t know about):

      The fertilized egg centrioles are donated from the sperm and must be cleared from the ova, or sterilization due to surplus centrioles occur. One protein removes a protective coat from the ova centrioles, and they are thereafter disassembled for good.

      http://phys.org/news/2016-05-critical-inheritance-dad-healthy-embryos.html

      1. Centriole degeneration during oocyte development is thought to be a handicap for the oocyte. It is a cell with enormous developmental potential and may be “tempted” to divide and form an embryo without waiting for the sperm.

        For the record, this precaution is not 100% reliable, because centrioles can be reconstituted. So unfertilized oocytes can form parthenogenetic embryos after all, though in mammals this development is doomed.

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